Acquiring the parts for the Duckiebot
✎Jacopo
The trip begins with acquiring the parts. Here, we provide a link to all bits and pieces that are needed to build a Duckiebot, along with their price tag.
In general, keep in mind that:
- The links might expire, or the prices might vary.
- In general, substitutions are OK for the mechanical components, and not OK for all the electronics, unless you are OK in writing some software.
Resources necessaries:
- Cost: USD ???
- Time: ??? days (average shipping)
Results:
- A kit of parts ready to be assembled.
Duckiebot configurations
✎Configuration D17-0: Only camera and motors.
Configuration D17-0+w: Previous one + an additional WiFi card (Edimax).
Configuration D17-1: LED lights and bumpers
Bill of materials
✎| Chassis | USD 20 |
| Camera with 160-FOV Fisheye Lens | USD 39 |
| Camera Mount | USD 8.50 |
| 300mm Camera Cable | USD 2 |
| Raspberry Pi 3 - Model B | USD 35 |
| Heat Sinks | USD 5 |
| Power supply | USD 7.50 |
| Class 10 MicroSD Card | USD 20 |
| Female/Female Jumper Wires (300mm) | USD 8 |
| Stepper Motor HAT - Mini Kit | USD 22.50 |
| GPIO Stacking Headers - DC motor hat headers 2x20 Stacking Extra Long | USD 2.50 |
| 16-Channel PWM/Servo HAT for Raspberry Pi - Mini Kit | USD 17.50 |
| Battery | USD 20 |
| 16 Nylon Standoffs (M2.5 12mm F 6mm M | USD 0.05/piece |
| 4 Nylon Hex Nuts (M2.5) | USD 0.02/piece |
| 4 Nylon Screws (M2.5x10) | USD 0.05/piece |
| Zip Ties 300x5mm | USD 8.99 |
| Joypad | USD 10.50 |
Premium Male/Male Jumper Wires (150mm) D17-1 |
USD 1.95 |
Wifi Augmenter D17-0+w |
USD 20 |
LEDs D17-1 |
USD 10 |
| GPIO Header - 40 pin female header | USD 1.50 |
LED HAT D17-1 |
USD |
| Bumpers | USD ?? |
| Total for minimum configuration | USD ?? |
| Total for fancy configuration | USD ?? |
Chassis
✎We selected the Magician Chassis as the basic chassis for the robot (Figure 1).
We chose it because it has a double-decker configuration, and so we can put the battery in the lower part.
The chassis pack includes the motors and wheels as well as the structural part.
The price for this in the US is about USD 15-30.
Raspberry PI 3 (RPI-3)
✎The RPI-3 is the central computer of the Duckiebot. Duckiebot version D17 uses Model B (Figure 2) (A1.2GHz 64-bit quad-core ARMv8 CPU, 1GB RAM), a small but powerful computer.
The price for this in the US is about USD 35.
Power Supply
✎We want a hard-wired power source (5VDC, 2.4A, Micro USB) to suppply the RPI-3 (Figure 3).
The price for this in the US is about USD 5-10.
Heat Sinks
✎The RPI-3 will heat up significantly during use. It is warmly recommended to add heat sinks, as in Figure 4. Since we will be stacking HATs on top of the RPI-3 with 15 mm standoffs, the maximum height of the heat sinks should be well below 15 mm. The chip dimensions are 15x15 mm and 10x10 mm.
Class 10 MicroSD Card
✎The MicroSD card Figure 5is the hard disk of the RPI-3. 16 GigaBytes of capacity are sufficient.
Camera
✎The Camera is the main sensor of the Duckiebot. Version D17 equips a 5 Mega Pixels 1080p camera with wide field of view ($160^\circ$) fisheye lens (Figure 6).
Camera Mount
✎The camera mount (Figure 7) serves to keep the camera looking forward at the right angle to the road (looking slightly down). The front cover is not essential.
300mm Camera Cable
✎A longer (300 mm) camera cable Figure 8 make assembling the Duckiebot easier, allowing for more freedom in the relative positioning of camera and computational stack.
Wifi Augmenter
✎The Edimax AC1200 EW-7822ULC wifi adpater Figure 9 improves the interactions with the Duckiebot by improving the connectivity between Duckiebot and laptop, especially useful in crowded environments (e.g., classroom).
Joypad
✎The joypad is used to manually remote control the Duckiebot. Any 2.4 GHz wireless controller (with a tiny USB dongle) will do.
The model link in the table (Figure 10) does not include batteries (2 AA 1.5V)!
DC Stepper Motor HAT - Mini Kit
✎We use the DC+Stepper motor HAT to control the motors that drive the wheels.
Male-Male Jumper Wires
✎
GPIO Stacking Headers
✎
16-Channel PWM/Servo HAT for Raspberry Pi - Mini Kit
✎
Battery
✎The battery provides power to the Duckiebot.
We choose this (Figure 15) battery because it has a good combination of size (to fit in the lower deck of the Magician Chassis), high output amperage (2.4A and 2.1A at 5V DC) over two USB outputs, a good capacity (10400 mAh) at an affordable price (USD 20).
Standoffs, Nuts and Screws
✎We use non electrically conductive standoffs (M2.5 12mm F 6mm M), nuts (M2.5), and screws (M2.5x10mm) to hold the RPI-3 to the chassis and the HATs stacked on top of the RPI-3.
In versions D17-0 and D17-0+w, the Duckiebot requires 12 standoffs, 4 nuts and 4 screws.
In version D17-1, the Duckiebot requires 16 standoffs, 4 nuts and 4 screws.
Ziptie
✎Two long (300x5 mm) zipties are going to be useful to keep the battery at the lower deck from moving around.
LEDs
✎In the fancy version D17-1, the Duckiebot is equipped with 5 RGB LEDs. LEDs can be used to signal to other Duckiebots, or just make cool patterns!
The pack of LEDs linked in the table above holds 10 LEDs, enough for two Duckiebots.
LED HAT
✎Daughterboard for Adafruit 16-Channel PWM / Servo HAT that enables connection with RGB LEDs, ADS1015 12 Bit, 4 Channel ADC, Monochrome 128x32 I2C OLED graphic display, and Adafruit 9-DOF IMU Breakout - L3GD20H + LSM303.
Female-Female Jumper Wires
✎
Bumpers
✎